In LTE-Advanced, in order to achieve a throughput exceeding that of LTE while maintaining backward compatibility with LTE, carrier aggregation (CA: Carrier Aggregation) has been adopted such that communication is performed by simultaneously using a plurality of carriers while using a bandwidth (up to 20 MHz) supported by LTE as a basic unit. For carrier aggregation, a carrier that is a basic unit is referred to as a component carrier (CC: Component Carrier).
The carrier aggregation is classified into three scenarios depending on frequency allocations, as illustrated in FIG. 1A, FIG. 1B, and FIG. 1C. FIG. 1A is the Intra-band contiguous CA, which is a scenario such that CCs that are contiguous within the band are to be allocated. This scenario is applied, for example, to a case where a wideband allocation, such as the 3.5 GHz band, is performed. FIG. 1B is the Inter-band non-contiguous CA where a plurality of CCs of different bands are arranged. This scenario is applied, for example, for a case where communication is performed by using a plurality of carriers, such as a 2 GHz band and a 1.5 GHz band. FIG. 1C is the Intra-band non-contiguous CA, which is a scenario where non-contiguous CCs within the same band are to be allocated. This scenario can be applied, for example, to a case where allocation of a frequency band to an operator is fragmented.
It is specified in the LTE system (which includes LTE-Advanced) that user equipment UE reports, for example, during connection to a network, its capability (Capability) to a base station eNB by a predetermined signaling message (UE-EUTRA-Capability) (Non-Patent Document 1).